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DS1307 is a hardware realtime clock, which works on I2C protocol. Better graphics using the same old fashioned alphanumeric LCD (type HD44780). Icons which shows the status for Alarm ON/OFF state, which gives a nice and cute look to the clock.

There are four switches connected to the uC, as shown in the figure. Function of the keys are same as clear from their names.

When the power supply is switched on it will give you the default date and time, but later you can change it to the desired value. After setting once, the backup battery will keep the clock ticking even after the power is not there.

A little about I2C:
There are basically four main conditions in I2C protocol.
1) Start Condition
2)Stop Condition
3)Data Validity

1)Start Condition:
when SCL is high and SDA H->L, will be taken as start condition for the communication.
2)Stop Condition:
when SCL is high and SDA L->H, will generate a stop condition.
3)Data Validity:
When SCL is high there should be no chande in SDA line only then the data is valid, the data change should be made only when SCL is low.

After sending of one byte of data the reciever has to acknowledge the sender for the successful reception. for this the sender make the SDA line high and reciever pulls down the SDA low, which tells the sender that data has reached safely.

Now the source code written in assembly, basically implements the I2C protocol. the assembly source written for Keil download here clock.asm and the direct hex file for programming the controller from here clock.hex. The schematic for the Digital clock is available in PDF format can be downloaded from here clock.pdf.

Project code has been revised and updated. Bug fixes regarding corrupt display.

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Tue Oct 06 2015, 08:22 AM
HI you looking for ideas or you have solution
Fri Oct 02 2015, 03:39 PM
poojitha: projects on wireless communication between two microcontrollers
Thu Oct 01 2015, 04:38 PM
hey! i wanted to simulate my circit using proteus. i have a sugar cube relay in my circuit....but i dont know which one is that in the device libraries of the software. any help? thankyou.
Tue Sep 29 2015, 09:40 PM
@Michal, that rocket is too heavy for itself and trust is not enough unless afterburners are fed with fuel properly.
Sat Sep 26 2015, 08:19 PM
Hello, its possible to make a amateur rocket with this engine, or something simillar, which be able to flight?
Thu Sep 24 2015, 10:38 AM
Ir Switch sir.
Wed Sep 23 2015, 01:10 AM
@engr1931 which project ?
Tue Sep 22 2015, 11:57 AM
Hello sir, is it ok to use 12.000MHz oscillator in IRswitch, because the requirement written in the post is 11.059MHz. And i use PIC1018 as an Ir receiver
Mon Sep 21 2015, 04:15 PM
Hello sir, your blog is kind of helpful for us especially students. May I know do you have the coding for decimal to binary using proteus 8. My mini project is about to convert decimal to binary just like a calculator. The output is LCD. A bit confusing is the decimal to binary coding on proteus 8. pls help thanks.
Sun Sep 20 2015, 09:08 PM
Have you searched our Embedded GSM Development and GSM and CDMA Discussion forums ?



Tue Oct 06 2015, 01:02 PM
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praveenraoms Avatar
Posted By praveenraoms
Tue Oct 06 2015, 01:06 PM
hi i want to know the code to access the geographi...
sachinmm Avatar
Posted By sachinmm
Wed Sep 30 2015, 08:54 AM
how to used polling method in this?? my code is co...
ajay_bhargav Avatar
Posted By ajay_bhargav
Tue Sep 29 2015, 09:39 PM
__irq is just compiler directive to wrap IRQ routi...
ajay_bhargav Avatar
Posted By ajay_bhargav
Tue Sep 29 2015, 09:36 PM
The comment does say the time values as per the th...
ajay_bhargav Avatar
Posted By ajay_bhargav
Tue Sep 29 2015, 09:33 PM
are you testing this on Proteus? or MplabX simulat...
ajay_bhargav Avatar
Posted By ajay_bhargav
Tue Sep 29 2015, 09:31 PM
[Topic moved to ARM Development Forum]
ajay_bhargav Avatar
Posted By ajay_bhargav
Tue Sep 29 2015, 09:29 PM
start with reading datasheet. SPI interface on LPC...
ajay_bhargav Avatar
Posted By ajay_bhargav
Tue Sep 29 2015, 09:27 PM
I am not sure you've solved it or not but "USARTRe...
ExperimenterUK Avatar
Posted By ExperimenterUK
Tue Sep 29 2015, 06:31 PM
i am confused in "__irq" it is uesd??sachin...
sachinmm Avatar
Posted By sachinmm
Tue Sep 29 2015, 11:11 AM
my I2C.c file=>>/*********************************...